<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    * {
      margin: 0;
      padding: 0;
    }
    html,body {
      width: 100%;
      height: 100%;
    }
    body {
      background: deepskyblue;
    }
    .box {
      width: 500px;
      height: 50px;
      margin:0 auto;

    }
    .box input {
      width: 400px;
      height: 50px;
      font:bold 20px/50px '宋体';
      box-sizing: border-box;
      padding-left: 10px;
    }
    a {
      display: inline-block;
      width: 80px;
      height: 44px;
      color:gold;
      text-align: center;
      padding: 3px;
      line-height: 44px;
      text-decoration: none;
      font-weight: bold;
      background: #666;
    }
    h1 {
      text-align: center;
      color:#fff;
      font:bold 50px/80px '幼圆';
      padding-top:200px;
    }
  </style>
</head>
<body>
  <h1>Open聊天室</h1>
  <div class="box">
    <input type="text" placeholder="请输入您的昵称">
    <a href="javascript:">进入房间</a>
  </div>

</body>
</html>